 /*******************************************************************************
  * Copyright (c) 2000, 2006 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.internal;

 import org.eclipse.jface.action.Action;
 import org.eclipse.jface.preference.PreferenceDialog;
 import org.eclipse.ui.IWorkbenchWindow;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.actions.ActionFactory;
 import org.eclipse.ui.dialogs.PreferencesUtil;

 /**
  * Open the preferences dialog
  */
 public class OpenPreferencesAction extends Action implements ActionFactory.IWorkbenchAction {

     /**
      * The workbench window; or <code>null</code> if this
      * action has been <code>dispose</code>d.
      */
     private IWorkbenchWindow workbenchWindow;

     /**
      * Create a new <code>OpenPreferenceAction</code>
      * This default constructor allows the the action to be called from the welcome page.
      */
     public OpenPreferencesAction() {
         this(PlatformUI.getWorkbench().getActiveWorkbenchWindow());
     }

     /**
      * Create a new <code>OpenPreferenceAction</code> and initialize it
      * from the given resource bundle.
      * @param window
      */
     public OpenPreferencesAction(IWorkbenchWindow window) {
         super(WorkbenchMessages.OpenPreferences_text);
         if (window == null) {
             throw new IllegalArgumentException ();
         }
         this.workbenchWindow = window;
         // @issue action id not set
 setToolTipText(WorkbenchMessages.OpenPreferences_toolTip);
         window.getWorkbench().getHelpSystem().setHelp(this,
                 IWorkbenchHelpContextIds.OPEN_PREFERENCES_ACTION);
     }

     /* (non-Javadoc)
      * Method declared on Action.
      */
     public void run() {
         if (workbenchWindow == null) {
             // action has been dispose
 return;
         }
         PreferenceDialog dialog = PreferencesUtil.createPreferenceDialogOn(null, null, null, null);
         dialog.open();
     }

     /* (non-Javadoc)
      * Method declared on ActionFactory.IWorkbenchAction.
      */
     public void dispose() {
         workbenchWindow = null;
     }

 }

